The 1999 Infiniti Q45 is available as a 4-door, 5-seat sedan. Starting at $48,200, the 1999 Infiniti Q45 Base is powered by a 4.1L , 8 -cylinder engine mated to an automatic transmission that returns an EPA estimated 17-mpg in the city and 24-mpg on the highway. The top of the line 1999InfinitiQ45Touring , priced at $ 49,900 , is powered by a 4.1L , 8 - cylinder engine mated to an automatic transmission that returns an EPA estimated 17-mpg in the city and 24-mpg on the highway.